> For the complete documentation index, see [llms.txt](https://developers-apps-in-toss.toss.im/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developers-apps-in-toss.toss.im/documentation/api-and-sdk-zh/sdk/domains-api/wen-jian/file.savebase64.md).

# File.saveBase64

> 函数式 API `saveBase64Data`也能用它实现相同功能。

### 功能说明

将 Base64 编码的数据以指定的文件名和 MIME 类型保存到用户设备上。可以保存图片、文本、PDF 等多种格式。 `fileName`中必须包含扩展名。

Toss 应用 Android `5.218.0`, iOS `5.216.0` 可在以上版本中使用。

### 类型

```ts
File.saveBase64(params: SaveBase64DataParams): Promise<void>;
```

**参数**

```ts
type SaveBase64DataParams = {
  data: string;
  fileName: string;
  mimeType: string;
};
```

**响应**

没有返回值。

### 示例代码

```js
import { File } from "@apps-in-toss/web-framework";

async function handleSave() {
  try {
    await File.saveBase64({
      data: "iVBORw0KGgo...",
      fileName: "some-photo.png",
      mimeType: "image/png",
    });
  } catch (error) {
    console.error("数据保存失败了:", error);
  }
}

document.querySelector("#save-file").addEventListener("click", handleSave);
```


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